Difluorosilanediyl-1,1'-bis(2,2,4,4,6,6-hexamethylcyclotrisilazane)

Lösliche, molekulare Titanosilicate

“…Die beiden peripheren Titanzentren sind in einer verzerrten trigonal-bipyramidalen Koordinationssphare von je funf Sauerstoffatomen umgeben und die beiden zentralen oktaedrisch von je acht. Obwohl kurzlich gezeigt werden konnte, daI3 JDF-L115] funffach koordinierte, quadratisch-planare Titanzentren enthllt, sollte darauf hingewiesen werden, daB funffach koordininierte Titanzentren in Titanosilicaten selten vorkommen. Demgegenuber sind die Titanzentren in Rutil[''' -einer Ti0,-Modifikationoktaedrisch koordiniert und ebenso in den synthetischen Titanosilicaten vom ETS-Typ.…”

Structure of 1,1'-fluoroboranediylbis(3-fluorodimethylsilyl-2,2,4,4,6,6-hexamethylcyclotrisilazane), C16H50BF3N6Si8

“…(1974), programs used: SHELXTL (Sheldrick, 1978) (2) 4060 (2) 3662 (3) 619 (12) N(2) -1884 (1) 3611 (2) 1784 (2) 480 (8) Si (2) -2172 (1) 2501 (1) 1631 (1) 436 (3) C (21) -3050 (2) 2538 (3) 971 (3) 686 (14) C (22) -2252 (2) 1918 (3) 2883 (3) 700 (15) N(3) -1520 (1) 1940 (2) 918 (2) 437 (8) Si (3) -752 (1) 2585 (1) 693 (1) 444 ( (32) 5 (2) 1874 (3) 230 (3) 794 (16) Si (4) -1587 (1) 808 (I) 609 (1) 606 (4) F (2) -2373 (1) 506 (1) 923 (2) 966 ( Discussion. Atomic coordinates and bond lengths and angles are given in Tables 1 and 2 The deviation of the ring conformation from the ideal boat form (torsion angles 0, 60, -60, 0, 60, -60 ° in cyclic order; Bucourt & Hainaut, 1965) is greater than that observed in previously determined structures of cyclotrisilazanes (Adamson & Daly, 1970;Clegg, Noltemeyer, Sheldrick & Vater, 1981), to the extent of approximating more closely to the twist conformation (33.1, 33.1, -70.6, 33.1, 33.1, -70.6°). Other cyclotris...…”

“…0108-2701/83/030389-03501.50 for crystallographic measurements on an automated Stoe X-ray four-circle diffractometer, cell dimensions determined by least squares from settings of 38 strong reflexions in range 20 < 20 < 25°; out of 3642 data collected between 20= 7 and 50 ° in a profile fitting mode (Clegg, 1981), 109 systematically absent (hOl, l-=2n+l; 0k0, k=2n+l) and 2190 unique (Rint-0-0194); structure solved by multisolution direct methods and refined anisotropically minimizing…”

(PhTe)3−: The Anionic Tellurium Analogue of I3−

“…16 3 , Z 4, F(000) 2636, 1 calcd 1.680 g cm À1 , m(Mo Ka ) 2.734 mm À1 , 2q max 468, T 160 K. A total of 8941 reflections were collected on a Stoe-Siemens four-circle diffractometer using graphite-monochromated Mo Ka radiation (l 0.71073), w/q scans, and on-line profile fitting. [31] Data were corrected for Lp effects and for absorption by y scans (transmission: 0.654 ± 0.485). The structure was solved by direct methods and refined by full-matrix least squares on F 2 to wR2 0.2637 for 7343 independent data and 607 parameters; R 0.0884.…”

“…This is in contrast to the diorganyltritellurides, which show significant [30] A detailed experimental description of the synthesis of 3 will be published elsewhere. [31] Unfortunately the small crystal size of the 1:1 complexes did not permit X-ray structure analysis.…”